Vacuum evacuation of a container may be used to preserve freshness of food or other perishables within the container. Vacuum evacuation may also be used to reduce gas volume to increase storage space for blankets, clothes, or other compressible contents within a container. Hand operated, or manual, vacuum devices can be light weight, of simple construction, and cheap to produce. Manual vacuum devices have been used to evacuate deformable and rigid containers and have also been used in conjunction with a variety of one-way valves to create evacuation systems.
One manual vacuum device has a two-stroke piston pump for evacuating deformable and rigid containers. The pump has a piston disposed inside a cylinder, the cylinder having a pluggable flexible vacuum cup disposed on a bottom end thereof. The piston has a peripheral check valve that allows gas to flow past the piston toward a cylinder cap. To evacuate rigid containers, the flexible vacuum cup is placed over a flexible check valve that is applied over access openings of the rigid containers. The flexible vacuum cup is prevented from completely collapsing under a pumping action by an inwardly projecting annular lip on a bottom end of the pump cylinder. The cylinder also has a pluggable port through a side wall of the cylinder to allow attachment of a flexible hose to aid in evacuating deformable containers.
Another manual vacuum device has a one-piece elastomeric end cap and vacuum cup assembly that fits around a bottom end of a cylinder. A suction cup on a bottom end of the assembly extends from an annular base that surrounds a central recess. The central recess defines an uncollapsible space between the bottom end of the assembly and a container surface.
Yet another manual vacuum device has a cylinder with a lower end that flares outwardly to define a frustoconical outer surface. A suction cup having a central aperture is disposed inside an end of the cylinder. A periphery of the suction cup extends radially past the flared end of the cylinder allowing the periphery of the suction cup to collapse, but leaving a central chamber defined by an uncollapsed central portion of the suction cup.
A still further manual vacuum device has a pump that attaches to a central portion of a container cover. The pump has a cylinder and a piston that has a peripheral check valve that allows gas to flow past the piston away from the container. The cylinder is press fit over a flange on the container cover such that a sealing engagement is accomplished between a face of the cylinder and the flange, as well as between an end surface of the cylinder and an upper surface of the cover.
Another manual vacuum device has an outer tube that telescopically slides on an inner tube, the inner tube having a piston at a top end thereof. The top end of the outer tube has a cap with a check valve for allowing gas to flow out of the outer tube. A bottom end of the inner tube is open and is press fit over a rigid one-way valve on a container. The piston has a central hole and a peripheral check valve that allows gas to flow past the piston toward the container and out of the pump through a space between the tubes. Pulling the outer tube away from the container creates a vacuum in the inner tube and pushing the outer tube toward the container forces gas out of the outer tube.
Another manual vacuum device has a piston with a peripheral check valve disposed in a cylinder. An elastomeric suction cup and an elastomeric valve housing are fitted over a bottom end of the cylinder. Moving the piston away from the suction cup draws a vacuum on the suction cup. Moving the piston toward the suction cup causes a one-way ball valve in the elastomeric housing to close and forces gas in the cylinder past the piston and out to the atmosphere through a hole in a top end of the cylinder.
A further manual vacuum device has a piston disposed in a cylinder for evacuating freezer bags. A conical nozzle having an axial passageway is attached at a wide end of the nozzle to an end of the cylinder. The piston has a peripheral check valve that allows gas to flow past the piston and away from the nozzle. The nozzle has four lateral passages near a narrow end thereof, the passages connecting the axial passageway to an outer surface of the nozzle. A check valve covers the nozzle axial passageway at the end of the cylinder allowing gas to enter the cylinder. A circumferential groove is disposed in the outer surface of the nozzle. The groove is positioned between the lateral passages and the wide end of the nozzle for the purpose of receiving an O-ring for tightly holding freezer bag walls against the nozzle.
A reversible manual vacuum device has a piston movable inside a cylinder for evacuating a bottle through a stopper that has a slit valve and is disposed in an open end of the bottle. The stopper has a peripheral flange and a raised annular wall extending upwardly from the flange. A bottom of the cylinder fits around the annular wall and contacts the peripheral flange. A piston disposed on an end of a hollow piston rod slides within the cylinder and a reversible one-way mushroom valve is disposed within a hole in the center of the piston. A reversible combination vacuum and pressure valve is also disposed in the stopper. Drawing the piston away from the stopper creates a vacuum in the cylinder. Pushing the piston toward the stopper forces gas through the mushroom valve, into the hollow piston rod, and out to the atmosphere through a hole in a top end of the piston rod.
Yet another manual vacuum device functions to draw a sudden vacuum on containers and bodily wounds. The pump has a hollow piston rod connected to a piston disposed in a cylinder. The cylinder has a closed end and a gas-flow orifice at an opposite end with a cup shaped end member having a central opening disposed over the orifice. The piston has a peripheral check valve that allows gas to flow past the piston toward the orifice. When the piston is drawn away from the orifice, gas in the volume between the piston and the closed end escapes past the check valve, travels through the hollow piston rod, and exhausts out of the piston rod to the atmosphere through a hole near a top end of the piston rod. When the piston is pushed back toward the orifice, the volume of gas between the piston and a top of the cylinder expands causing a vacuum to be created. As the piston nears the orifice, the hole in the piston rod comes into communication with the volume of gas between the piston and the closed end of the cylinder, which causes a sudden vacuum to be drawn on the orifice.
A manual vacuum evacuation system has a rigid check-valve in a bag wall and a pump for evacuating gas from the bag. The check-valve has an inner part that extends through a hole in the bag wall and threadably mates with an outer part of the check-valve to squeeze the bag wall and a flat holding washer therebetween. The pump has a cylinder and a piston disposed in the cylinder, the piston having a peripheral check valve. An open end of the cylinder has an annular flange over which fits an elastomeric ring. The ring has an annular wall extending from a bottom side of the ring, the annular wall being placed against a surface of the flat washer to seal the pump to the valve.